I just checked again, and the WMR/TfW Only Super Off Peak Euston-Manchester return fare has these restrictions, from BRFares, copy pasted:
Full details of all British rail Single, Return & Season tickets and Travelcards. Built-in Season Ticket Calculator.
www.brfares.com
Not valid on trains timed to depart Manchester Piccadilly after 04:29 or before 10:30 and not between 16:00 to 19:00.
Not valid on trains timed to depart London Euston after 04:29 or before 10:30 and not between 16:00 to 19:00.
With a ticket type restriction barring BoJ on the outward.
The TVM summary lines (which are in the electronic restriction bit) read thus and so are (astonishingly) different:
VALID ON DEP BETWEEN 1031-1531 & AFTER 1930
VALID ON DEP BETWEEN 1031-1531 & AFTER 1930
While the electronic restrictions only actually implement departure from Euston/Picc and don't act against other stations. They are also different again!
Dep from Euston - 1046-1549 and 1946 (1947 on return!) or later
Dep from Picc - 1031-1531 and 1931 or later
Of course these might have the same effect depending on the actual times of the trains.
What were you suggesting they were?
Either way it's a mess!